学科：水文学及水资源,出版时间：2017,导师：钱会指导,学位授予单位：长安大学,论文作者：杨超著,
中文
随着我国经济快速发展，能源形势变得日趋严峻，节能减排的呼声日益高涨，浅层地温能作为一种重要的新型清洁能源，它的开发利用对构建资源节约型和环境友好型社会具有非常重要的意义。浅层地温能资源不仅能够代替燃煤作为一种新型能源被开发利用，而且具有很好的社会效益，作为一种清洁型能源，浅层地温能的利用可减少大量的污染性气体排入大气。近年来随着工业化过多燃烧化石能源，大量排放出二氧化碳气体，引起全球温室效应不断加重，气温不断升高。在我国北方，冬季各大城市雾霾天气频繁出现，其中供暖锅炉燃煤污染是造成这一现象的重要诱因。银川市作为宁夏回族自治区的省会城市，近年来随着城市的不断发展，城市空气质量也在不断下降，根据相关部门监测分析，银川大气环境已经出现轻度、中度污染。本文在对银川市水文地质条件、地热地质条件及浅层地温能开发利用现状进行调查的基础上，开展银川市555㎞²范围内浅层地温能适宜性分区研究，对研究区内浅层地温能热容量、浅层地温能换热功率、浅层地温能开发潜力、浅层地温能开发利用产生的经济效益和环境效益进行评价，在此基础上选择一处地埋管地源热泵工程，对热泵工程制冷与供暖时期换热孔周围的地温及热泵机组的能耗数据进行监测，分析换热孔周围地层温度变化情况，评价热泵运行能效系数、节煤量及减排效果，以实际热泵工程运行效果分析银川市浅层地温能开发利用前景。 本文通过野外调查、资料整理、样品采集、野外试验、室内样品分析、实时数据监测等手段对银川市浅层地温能进行综合评价，主要研究成果如下： (1)通过在银川地区开展多处热响应试验测试及岩土体样品热物性测试研究工作，分析银川地区200m以浅地热地质条件及地温场特征。获取研究区内200m以浅地层平均初始温度约为13.77℃，地层平均热传导系数约为2.11W/(m.k)，地层每延米吸热量约为61.84W/m，每延米放热量约为25.22W/m。 (2)对研究区范围内浅层地温能开发利用适宜性进行研究。以所获取的最新水文地质条件及热物性参数等影响因素，进行地下水地源热泵及地埋管地源热泵适宜性分区，其中地下水地源热泵较适宜区面积为232.42㎞²，不适宜区的面积约为210.70㎞²；地埋管地源热泵适宜区面积约114.22㎞²，较适宜区面积约为328.91㎞²。 (3)对研究区内浅层地温能定义深度地层地层热储量进行研究。采用热储法计算555㎞²范围内200m以浅地层总热容量为2.46×10¹⁴KJ/℃，与全国各省会城市相比，银川地区单位面积热容量接近省会城市平均单位面积热容量，资源储量较理想。综合考虑银川地区多层结构的含水层分布特点及地下水水质情况，避免地埋管换热孔施工过程中过深的钻孔引起地下水串层，对研究区100m深度内浅层地温能热容量进行研究，采用热储法进行分区计算，将研究区内100m深度热容量的分布情况可视化，可视化结果将研究区分为三个区，总热容量值为1.231×10¹⁴KJ/℃。 (4)在适宜性分区的基础上开展浅层地温能资源量分区评价，分析浅层地温能资源量空间分布，分别对地下水地源热泵与地埋管地源热泵两种开发利用方式的浅层地温能换热功率进行分析，银川地区地埋管地源热泵在资源量上优于地下水地源热泵。研究区内两种开发利用方式的综合换热功率分析结果介于地下水地源热泵换热功率与地埋管地源热泵换热功率之间。 (5)根据浅层地温能资源量分析结果对研究区内浅层地温能可利用量进行研究，地下水地源热泵每年总可利用量为9.11×10⁶GJ。地埋管地源热泵每年总可利用量为5.95×10⁷GJ。研究区内地下水地源热泵及地埋管地源热泵综合开发利用年总可利用量为4.14×10⁷GJ。地下水地源热泵每年总可利用资源量的经济效益为1.O7亿元，地埋管地源热泵每年总可利用资源量的经济效益为6.95亿。综合可利用资源量每年经济效益可达4.84亿元。 (6)以浅层地温能35％的利用率评价浅层地温资源可利用量的减排量，研究区内进行浅层地温能开发利用的环境效益显著。地下水地源热泵可减少二氧化碳排放量约为4.33×10⁵t/a，节约环境治理费为0.5亿元/年。地埋管地源热泵可减少二氧化碳排放量为2.83×10⁶t/a，节约环境治理费3.34亿元/年。地下水地源热泵和地埋管地源热泵综合开发浅层地温能可减少的二氧化碳排放量可达1.97×10⁶t/a，节约环境治理费2.33亿元/年。 (7)研究发现银川地区的地层特征使得地埋管换热过程中对周围地层温度的影响在垂向上存在一定差异，随着热泵工程的运行，在地下水渗流作用较强的层段地层温度变幅会明显高于其它层段，且换热孔对周围地层温度影响范围较远，影响范围达5m。其它深度地层的温度变化较平稳，温度影响范围约为3m。热泵工程在经过长期制冷和供暖后地层温度基本保持平衡，仅在部分层段出现轻微热堆积，热泵工程在运行十年后仍满足建筑制冷与供暖需求，该工程在制冷与供暖时具有明显的节能减排效果，因此可将地埋管地源热泵技术作为银川市浅层地温能开发利用的主要手段。 关键词：浅层地温能；适宜性分区；地层热容量；换热功率；开发潜力；银川地区；
英文
With the rapid development of Chinese economy, the energy situation is becoming more and more serious, which derives an increasing requirement for energy-saving and emission reduction. Shallow geothermal, as a very important novel clean energy, is much meaningful for building a resource-saving and environment-friendly society when it is exploited. The resource can not only be used as a new energy instead of coal, but also have good social benefits for reducing a large amount of pollution gas into the atmosphere. In recent years, a huge portion of carbon dioxide emissions has made temperatures keep rising and triggered a series of environmental problems. Especially in winter in Northern China, fog and haze frequently appears in the northern city due to massive utilization of fossil energy such as coal. As the capital city of Ningxia Hui Autonomous Region, the air quality in Yinchuan is declining in recent years with the urban development. Light and moderate pollution in atmospheric environment has appeared based on monitoring data from relevant departments in Yinchuan. In this paper, the suitability partition of shallow geothermal energy was conducted and the heat capacity, power of heat transfer, exploitation potential, economic and environment benefit of shallow geothermal energy are also evaluated in the 555km area in Yinchuan city, based on the investigation of the hydrogeological conditions, geothermal geological conditions and the development and utilization of shallow geothermal energy. After that, an existing ground-source heat pump project was selected to monitor the temperature and heat pump energy consumption in the period of cooling and heating, the ground temperature changes around the buried pipe was analyzed and the energy efficiency coefficient, the coal saving and the emission reduction effect of the heat pump was evaluated finally. In this paper, the methods including field investigation, data collection and compilation, sample data analysis, field tests and data monitoring are used to evaluate the shallow geothermal resource in Yinchuan city comprehensively. Conclusions are summarized as follows: (1)In-situ thermal conductivity tests and thermos-physical properties tests of rock-soil samples in Yinchuan city are carried in several regions to analyze the geothermal conditions and temperature field features in the depth of 200m. The initial temperature is 13.77 ℃. The average heat transfer coefficient is approximately 2.11 W/ (m.k). The amount of formation heat absorption and heat release is about 61.84W/m and 25.22 W/m. (2)The suitability partition of the shallow geothermal energy is conducted based on hydrogeological conditions and thermal parameters in the study area. The general suitable area of groundwater heat pump is 232.42㎞², and non- suitable area is about 210.70㎞²; the suitable area of ground-coupled heat pump is about 114.22㎞², and general suitable area is about 328.91㎞². (3)The total heat capacity in 200m depth is 2.46×10¹⁴KJ/℃ by calculation using volumetric approach in the range of 555 ㎞², the heat capacity per area is consistent with the average value of the capital cities in China. The heat capacity in 100m depth was partitioned into three zones according to visualization result of heat capacity distribution, and the total heat capacity is 1.231×10¹⁴KJ/℃ by calculation. (4)The distribution of shallow geothermal energy in space was analyzed. The heat power of two ways of geothermal utilization including the groundwater source heat pump and ground-coupled heat pump was analyzed, results shown that ground-coupled heat pump is better than groundwater heat pump in terms of resource amount. Considering the combination of two ways of utilization, the comprehensive heat transfer power was evaluated and the result falls in the middle of the above two ways. (5)The available geothermal amount was analyzed based on the results of resource analysis of shallow geothermal energy. The total available amounts of ground water source heat pump and the ground-coupled heat pump is 9.11×10⁶GJ and 5.59×10⁷GJ per year, with the economic benefits of 107 million yuan and 695 million yuan respectively. The total available amount of comprehensive utilization of above two ways is 4.14×10⁷GJ per year, with the economic benefit of 484 million yuan per year. (6)The emission reduction was evaluated with the utilization rate of 35% of shallow geothermal energy, the results confirm the apparent improvement of environment when utilizing shallow geothermal energy. The utilization of groundwater source heat pump can reduce the carbon dioxide emission by 4.33×10⁵ t/a, saving environmental management fee of 50 million yuan per year. The utilization of ground-source heat pump can reduce the carbon dioxide emission by 2.83×10⁶ t/a, saving environmental management fee of 334 million yuan per year. The comprehensive utilization of shallow geothermal energy can reduce the carbon dioxide emissions by 1.97×10⁶t/a, saving environmental management fee of 233 million yuan per year. (7)It is found that in the process of ground-source heat transfer, there are some differences in the influence of the surrounding formation temperature in vertical direction due to the stratigraphic characteristics in Yinchuan area. With the operation of the heat pump project, the strata temperature variation in the strong seepage layer is greater than that in other layers, and the temperature influential distance of heat transfer hole in the layer is 5m, which is relatively farther than that in other layers with 3m. The formation temperature is basically constant after the heat pump project in the long-term cooling and heating, and slight heat accumulation phenomenon appeared in certain depth of the formation. After running for 10 years, the project can still meet the building refrigeration and heating needs. Therefore, ground-source heat pump project can be selected as the primary technology to utilize the shallow geothermal energy. Keywords: shallow geothermal energy, suitability division, formation heat capacity, heat transfer power, development potential, Yinchuan region
